Method of forming pipe loops



Oct. .22, 1929. o. M. SUMMERS 3 ,3

IETHOD OF FORMING PIPE LOOPS File d Jan. 1, 1927 2 Sheets-Sheet 1 Z/JZZ/ ,29 m A Maw attoznu;

Oct. 22,1929. 0. M. SUMMERS 1,732,343

METHOD OF FORMING PIPE LOOPS Filed Jan- 51. 1921 2 Sheets-Sheet 2 (i 6i 4i) (i) ii);

Patented Got. 22, 1929 STATES PATENT OFFICE OTTO M. SUMMERS, OF DAYTON, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

FRIGIDAIRE CORPORATION, A CORPORATION OF DELAWARE METHOD OF FORMING PIPE LOOPS Application filed January 31, 1927. Serial No. 164,880.

a plurality of loops adapted to contain liquid refrigerant connected therewith. The greater the number of loops that can be used, the greater is the cooling surface presented. Loops are used, as they present their entire surface to the atmosphere and, at the same time, provide a free passage for the circulating air within the cooling compartment.

If a sufficient number of round loops were used, it would be necessary to place them so close together that the circulation of air through cooling unit would be materially obstructed. For this reason it is preferable to use loops which are flattened throughout most of their length. However, it is desirable that the loops have cylindrical ends so that they may be more readily attached to header, because it is easier to make a good joint between cylindrical parts than between parts which are oblong or elliptical in cross-section.

It is an object of this invention to provide a method of manufacturing a plurality of individual loops from a single coil of pipe, in which a portion of each of these loops has one cross-sectional contour and another portion another cross-sectional contour.

A further object of this invention is to pro vide a method for making a plurality of pipe loops which can be practiced by means of single and easily constructed apparatus.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is an elevation of a pipe coiled about a mandrel in the first step of the operation.

Fig. 2 is a sectional view taken on the line 22 of Fig. 1.

Fig. 3 is a fragmentary view showing a forming operation.

Fig. 4; is a sectional view taken on the line 1- 1 of Fig. 3.

Fig. 5 is a fragmentary view with the forming dies removed from mandrel showing saw cut through pipe.

Fig. 6 is a sectional view taken on the line 6-6 of Fig. 5.

Fig. 7 shows one of the completed loops attached to a header.

Fig. 8 is a sectional View taken on the line 8-8 of Fig. 7.

Referring to the drawings, a length of flat pipe 10 is coiled about a mandrel 11. The mandrel may be of any suitable shape to conform with the configuration of the finished product. The top side of the mandrel is provided with a groove 12 which extends the entire length of the mandrel intermediate the edges thereof. The groove 12 is-adapted to receive a die or swaging member 13. The die or swaging member is provided, transversely thereof, with spaced,'semi-circular grooves 14;, each of which receives a turn of the coiled ipe. The die or swaging member 13 is then elevated above the plane of the mandrel 11, by means of a removable bar or wedge 15, thereby providing a space between the top of the mandrel and the pipe 10. This space is provided in order to permit shaping a portion of each turn of pi e into a cylindrical form without deforming other portions thereof.

In practice, it is preferable first .to assemble the die or swaging member 13 and wedge 15 in the mandrel 11, and then wrap the pipe 10 about the assembly. This permits the turns of the pipe to be uniformly spaced by the semi-circular grooves 14. A second die or swaging member 16, which is similar to the member 13, is then placed in an inverted position upon the turns of the coiled pipe 10, so that the grooves of each of the die or swaging members are opposite, with each pair of grooves having a portion of a turn of the coil between them.

By means of a press (not shown), the die or swaging member 16 is forced downwardly portion of the pipe which is between these members into a cylindrical shape. The space which is provided between the mandrel 11 and the pipe 10, permits the formation of a shoulder on the underside of the pipe turn, as is clearly shown at 17 in'Fig. 3.

The die 01 swaging members 16, 13, and the wedge 15 are then removed and the rounded portions of the pipe which have been formed are severed, as shown at 18, by any suitable means, such as a saw 20. The natural spring of the loops thus formed, permits them to be easily removed from the mandrel; and, as they are usually constructed of copper, each loop may be readily bent by hand into the desired shape to fit into the opening in header shown in Fig. 7. It is readily apparent that the process described may be employed in any case where it is desirable to provide end portions of one cross-section on pipe loops of another cross-section by the use of suitable die or swaging members.

WVhile the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. The method of manufacturing pipe loops having portions of different cross-sectional contours comprising, forming a length of pipe into a'coil having a plurality of convolutions, changing the cross-sectional contour of a portion of each convolution, then severing the coil at the portions thereof which have been changed in cross-section, to provide a plurality of individual pipe loops.

2. The method of manufacturing pipe loops having portions of different cross-sectional contours comprising, forming a length of flattened pipe into a soil having a plurality of convolutions changing the cross-sectional contour of a portion of each convolution, then severing the coil at the portions thereof which have been changed in cross-section, to provide a plurality of individual pipe loops.

3. The method of manufacturing pipe loops having portions of different cross-sectional contours comprising, forming a length of flattened pipe into a coil having a plurality of convolutions, rounding a portion of each convolution, then severing the coil at the rounded portions to provide a plurality of individual pipe loops.

4. The method of manufacturing pipe loops having portions of different cross-sectional contours comprising, forming a length of flattened pipe into a coil having a plurality of convolutions, rounding a portion of each convolution, then severing the coil intermediate the ends of the rounded portions to provide individual pipe loops each hav- :ing end portions of rounded cross-section and an intermediate portion of flattened crosssection.

5. The method of manufacturing pipe loops having portions of different cross-sectional contours comprising, spirally winding flattened pipe about a mandrel to provide a coil having a plurality of convolutions, si-

multanecnsly rounding a portion of each eonvolution, and severing the coil through the rounded portions to provide individual pipe loops each having end portions of rounded cross-section and an intermediate portion of flattened cross-section.

6. The method of manufacturing pipe loops which consists in forming pi 3e into a turn having portions adapted to 'orm the ends of an open loop and swaging said portions to produce a desired cross-sectional contour.

7. The method of manufacturing pipe loops which consists in forming pipe into a plurality of turns each having portions adapted to form the ends of an open loop and simultaneously swaging said portions to produce-a desire-d cross-sectional contour.

8. The method of manufacturing pipe loops which consists in forming pipe into a turn having portions adapted to form the ends of an open loop and deforming a portion only of said turn to produce a loop having portions of difierent cross-sectional contours.

In testimony whereof I hereto affix my signature.

OTTO M. SUMMERS. 

